Expanding tube seal for floating roof structures

ABSTRACT

An expanding tube seal for floating roof structures wherein a tube is enclosed within and protected by a scuff band supporting the tube from the roof structure, said expanding tube seal being capable of sealing the rim space between the floating roof structure and the wall of a storage tank or the like within predetermined limits of maximum and minimum rim spaces, and mechanical means engaging with the undersurface of said tube seal to prevent excessive sag of said tube and thereby increase the horizontal reach of said tube seal.

United States Patent [1 1 McKibbin 1 Apr. 3, 1973 [54] EXPANDING TUBE SEAL FOR FLOATING ROOF STRUCTURES [75] Inventor: Dean K. McKibbin, Warren, Pa.

[73] Assignee: Pittsburgh-Des Moines Steel Company, Pittsburgh, Pa.

22 Filed: May 4,1971

[21] Appl.No.: 140,055

52] U.S. Cl. ..220/26 R, 220/26 SA 51 im. Cl. ..B65d 87/18 58 Field 6: Search ..220/9 R, 26 R, 22.1, 26 s,

[56] References Cited UNITED STATES PATENTS FlIlO ..220/26 SA Fino ..220I26 SA Maeder et al. ..220/26 S Primary Examiner-Lloyd L. King AttorneyShoemaker & Mattare [57] ABSTRACT An expanding tube seal for floating roof structures wherein a tube is enclosed within and protected by a scuff band supporting the tube from the roof structime, said expanding tube seal being capable of sealing the rim. space between the floating roof structure and the wall of a storage tank or the like within predetermined limits of maximum and minimum rim spaces, and mechanical means engaging with the undersurface of said tube seal to prevent excessive sag of said tube and thereby increase the horizontal reach of said tube seal.

25 Claims, 7 Drawing Figures PATENTEDAPRB I975 SHEET 1 [IF 3 FIGJ.

INVENTOR DEAN K. MCKIBBIN BY M MM.

C/ANEYS PATENTED RE I975 SHEET 2 OF m F/G.4.

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INVENTOR DEAN K. McKIBBIN ATTORNEYS PATENTEDAPR 3 I975 3, 724.705

SHEET 3 0F 3 ATTORNEYS EXPANDING TUBE SEAL FOR FLOATING ROOF STRUCTURES BACKGROUND OF THE INVENTION This invention relates to an expanding tube seal for floating roof structures wherein an annular flexible tube filled with a suitable fluid material is supported in the rim space between a floating roof structure anda wall of a storagetank or the like to define an annular sealing ring means for sealing the rim space between the floating roof structure and storage tank wall to 'prevent loss of product stored in the tank due to evaporation and the like and to reduce the hazard of fire or explosion when the stored product is a volatile material such as petroleum or the like. Such expanding tube seals are capable of sealing rim spaces of varying width, the space capable of being sealed varying generally from a minimum of 3 inches to a maximum of 15 inches with the present invention.

In larger storage tanks, such as are becoming increasingly more in demand, and where the diameter of the tank often exceeds 250'feet, the rim space between the floating roof and shell or wall of the tank must be proportionately increased to accommodate variations in the rim space due to constructional variations and out of roundness of the shell and uneven settling of the tank and the like. With conventional tube seal means for sealing the rim space, the maximum rim space which can be effectively sealed is approximately inches, and with the larger tanks and the resulting larger rim spaces, the variation in rim spaces due to tank imper' fections and the like, as noted above, often ranges from 3 inches minimum to inches maximum, and conventional systems are accordingly not capable of sealing the larger rim spaces.

The present invention provides a movable mechanical means engageable at the bottom of the expanding tube seal for reducing the natural tendency of the tube to sag and thereby substantially increasing the horizontal reach of the expanding tube seal for effectively sealing greater rim spaces. The tube is enclosed within a protective scuff band for supporting the tube from the floating roof and the tube is filled with a fluid such as kerosene or the like. If the seal is to be used in a nonfreezing environment, water may be used rather than kerosene, or any other suitable fluid may be used. The weight of the fluid filled tube causes the seal and support means to move outwardly toward the shell of the tank to effect a seal between the roof and tank at all times. The scuff band protects the tube against abrasion or other damaging contact with the roof or tank shell and prevents loss of the sealing fluid.

According to one embodiment of the invention, the tube seal comprises a plurality of individual tubular bags closed at opposite ends and disposed in end-toend relationship to define a continuous, annular sealing ring means around the periphery of the floating roof. The volumes inside adjacent tubes then may be allowed to communicate, as through interconnecting piping or the like, to permit the'flow of sealing fluid from regions around the tank'periphery where the annular space is tight, to regions where the annular space is less tight.

OBJECTS OF THE INVENTION It is an object of this invention to provide an expanding tube seal having mechanical means in supporting engagement therewith for increasing the horizontal reach of the expanding tube seal.

Another object of this invention is to provide an expanding tube seal supported from a floating roof structure by means of a flexible scuff band and having mova ble mechanical means engageable at the underside thereof for reducing the natural tendency of the tube to I which tube seal which comprises a continuous, annular ring filled with a fluid material.

A still further object is to provide an expanding tube seal comprising a one-piece tubular member filled with fluid with its opposite ends closed and overlapped to define an annular sealing ring.

An even further object of this invention is to provide an expanding tube seal which comprises a plurality of closed tubular members or bags, with the bags arranged end-to-end in an annular ring around the floating roof and with adjacent ends in communication one with the other as through piping means to provide in effect, a continuous annular sealing ring. The communicating means provides for relieving of pressure within the bags due to the local variations in rim space caused by movement of the floating roof or tank out of roundness or the like.

Yet another object of the invention is to provide a tubular sealing ring wherein individual portions thereof may be replaced if damaged without disturbing other portions of the sealing ring.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view partlybroken away of a floating roof structure and storage tank with an expanding tube seal according to the present invention interposed between the floating roof structure and storage tank and sealing a nominal rim space with the roof moving upwardly relative to the tank shell.

FIG. 2 is a top perspective view of a first form of the tube for an expanding tube seal.

FIG. 3 is a top perspective view of a second form of the tube for an expanding tube seal.

FIG. 4 is an enlarged sectional view of a portion of the structure shown in FIG. 1, illustrating the position of the expanding tube seal for sealing a nominal rim space and a minimum rim space in phantom lines and in full lines, respectively, with the roof moving up wardly relative to the tank shell.

FIG. 5 is a view of the scuff band, tube, and mechanical means in the form of a support angle structure, looking toward the outer surface of said scuff band and tube and showing the overlap of the scuff band sections.

FIG. 6 is an enlarged sectional view similar to FIG. 4, but showing the expanding tube seal sealing a maximum rim space with the roof moving downwardly relative to the tank shell.

FIG. 7 is a top perspective view of one form of the invention wherein a plurality of individual tubular bags are disposed in overlapping end-to-end relationship about the periphery of the roof, and showing one of the bags removed for repair or replacement, with the remaining bags undisturbed.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, wherein like reference numerals refer to like parts throughout the several views, an expanding tube seal according to the present invention is indicated generally at 1 and is interposed in the rim space between a floating roof structure indicated generally at 2 and the inside surface of the side wall of a storage tank indicated generally at 3.

The storage tank 3 comprises a bottom wall 4 and a cylindrical, upstanding side wall 5 around the marginal edge of the bottom wall 4. The floating roof structure 2 comprises a substantially flat planar cover 6 having a hollow, annular pontoon section 7 connected about the periphery thereof and having a bottom wall 8, peripherally upstanding outer side wall 9, a cylindrical upstanding inner side wall 10, and a top wall or cover 11. The outer side wall 9 has a radially inwardly offset portion 12 at the bottom marginal edge thereof defining a clearance notch N around the bottom marginal edge of the pontoon structure 7.

A suitable weather shield means 13 is bolted around an inner marginal edge 14 thereof to a radially inturned flange 15 on the upper marginal edge of the side wall 9 of the pontoon and is in sliding sealing contact at its outer peripheral edge 16 with the inside surface of said wall 5 of the storage tank 3.

The tube seal 1 comprises an annular, hollow flexible tube 17, preferably made of urethane or Buna N coated nylon or the like and filled with a suitable fluid F such as kerosene or the like. In a typical storage tank, the tube 17 would preferably have a diameter of about 14 inches and a wall thickness of about 0.040 inches.

The tube 17 is supported on the floating roof structure 2 by means of a scuff band 18 made of a suitable flexible and wear-resistant material. The scuff band comprises a plurality of rectangular sections A, B, C, D, etc., extended at their upper ends between flange 15 on side wall 9 and bottom edge 14 of weather seal 13 and suitably fastened or clamped between flange 15 and the edge 14 of weather seal 13 by means of a top bolting bar or ring 19 bolted to the flange 15 in overlying relation to the edge 14 of weather seal 13 and the top ends of the scuff band sections as by bolts B or the like. The lower or bottom ends of the scuff band sections are extended around said tube 17 and turned downwardly between a bottom bolting bar or ring 20 and the bottom marginal edge of side wall 9 of pontoon 7 and suitably clamped therebetween as by means of bolts or the like 21 extended through the ring 20, scuff band 18 and edge of side wall 9. In a typical installation, the scuff band sections A, B, C, D, etc. are preferably overlapped at their adjacent edges approximately 24 inches to provide a continuous support for the tube 17 about the circumference of the pontoon 7. The scuff band encloses and protects the tube from abrading contact with the wall 5 of tank 3.

A plurality of downwardly extending support braces 22 are welded or otherwise suitably secured at their upper ends to the bottom of pontoon 7 about the bottom marginal edge thereof in the clearance notch N and are suitably braced by a plurality of inclined, upwardly extending knee braces 23 welded or otherwise suitably fixed to each of the support braces 22 adjacent the lower ends thereof and to the bottom 8 of pontoon 7. A support arm 24 is suitably pivotally connected at its lower end to the lower end of each of the support braces 22 by means of a pivot pin or the like 25 extended therethrough. As seen in FIG. 5, the pivot pin comprises a bolt 26 loosely received through aligned openings 27 and 28 in the flanges 29 and 30 of support brace 22 and support arm 24 and retained therein by means of a cotter pin 31 and washer 32. A plurality of circumferentially extending support angles 33 are welded or otherwise suitably secured to the upper ends of the support arms 24 at an angle relative to the axis of the arms, with the support angles disposed in end-toend relationship and with a pair of support arms secured to each support angle adjacent the opposite ends thereof so that two support arms are connected with each support'angle to define a plurality of independent support means about the periphery of the roof. The support angles may be arcuate or straight sections, as desired. A suitable means such as bolts 34 or the like are-extended through one flange 35 of each support angle 33, through the scuff band 18, and through a bot-. tom bolting bar 19a for holding the scuff band in position relative to the support angles. The length of scuff band between bolts 34 and bolts 21 limits the outward horizontal movement of the tube seal and scuff band relative to the roof. The support angles 33, support arms 24 and support braces 22 provide vertical support for the relatively heavy tube 17 to prevent it from sagging or dropping excessively, and thus substantially increase the reach of the tube seal and the maximum rim space which can be effectively sealed thereby. As

the rim space between the floating roof structure and the side wall of the tank or the like changes, the support arms 24 pivot inwardly or outwardly along with movement of the tube seal to provide support thereof at all times and to accommodate the tube seal to structures having different or varying rim spaces. As seen in FIGS. 1 and 4, when the seal is not extended to its maximum reach, the tube seal droops on opposite sides of the angles 33 to form troughs and effect a good seal in all positions of the seal.

A relatively short, laterally outwardly extending bumper 36 is welded or otherwise suitably secured to each support arm 24 adjacent the upper end thereof for engagement with the side wall 5 of tank 3 when the rim space is at a minimum, as seen in full lines in FIG. 4, to protect the tube seal against damage.

Similarly, a relatively short rectangular plate or inner bumper bar 37 is welded at the upper end of each support brace 22 and extends horizontally to engage and limit inward movement of the support arms 24 to prevent pinching of the scuff band or tube when the rim space is at a minimum.

In FIG. 2 a first form of tube 17 is illustrated and the tube comprises an endless, annular tubular ring,

. preferably filled with a fluid material such as kerosene scuff band by extending the bolts B through bolt holes 40 in the ends 17a and 17b.

The ends 17a and 17b provide hollow accumulator volumes into which the sealing fluid can expand to relieve pressure in the tube 17 when the sealing fluid expands, as for example would occur if kerosene was used as the sealing fluid and was put in the tube in a cool condition and then heated due to an increase in ambient temperature.

Referring now to FIG. 6, the action of the tube seal when the roof is moving downwardly within the storage tank is diagrammatically illustrated. As can be seen in this figure, the portion 41 of the scuff band extending from the support angle to the top of the floating roof is slack and the portion 42 of the scuff band extending from the support angle to the bottom of the floating roof is relatively tight due to the upward frictional drag of the side wall 5 on the scuff band 18. The tube seal is show sealing a maximum rim space with the support arm and support angle engaging the bottom of the tub and providing vertical support therefor to prevent the tube from drooping and falling out of engagement with the side wall 5 of the storage tank 3. The length 42 of scuffband between the support angle and the bottom of the roof limits the outward movement of the tube seal relative to the roof and is selected such that the tube seal will effectively seal at least a inch rim space.

In FIG. 7, a further form of the invention is shown and the tube comprises a plurality of individual tubular bags 43 similar to seal 17' with each bag closed at its opposite ends 43a and 43b and with the opposite ends folded upwardly and bolted to the flange 15 on the top of the floating roof along with the scuff band and weather seal. The adjacent ends of the bags 43 are overlapped so as to define a continuous tubular seal about the periphery of the floating roof. The scuff band is removed from this figure for purposes of illustrating the individual bags comprising the tubular seal.

A suitable interconnecting means, such as pipes 44 or the like, are provided at adjacent ends of adjacent bags 43 to establish fluid communication between adjacent bags so that sealing fluid may flow from one bag into an adjacent bag to permit the flow of sealing fluid from regions around theperiphery. of the tank where the rim space is small or tight, to regions where the rim space is larger.

A damaged bag 43 is shown being removed from the floating roof for repair or replacement and as can be seen, the remaining bags comprising the tubular seal are left undisturbed. Accordingly, if repair or replacement of one of the bags becomes necessary, only the would be spaced radially outwardly approximately one half inch from the plane of the edge of the floating roof.

sealing fluid in that particular bag will be required to be i drained from the seal and the sealing fluid in each of the remaining bags is left intact.

By way of specific example, an expanding tube seal constructed in accordance with the present invention port arms 24 would be approximately 24% inches below the edge of the bottom bolting bar or ring and Each support arm would be approximately 23% inches long from the pivot to the outside corner of the support angles and would comprise a 1 /2 X 1% X% inch angle. The support angles secured to the upper ends of the support arms would be approximately 10 feet long and would be attached to the support arms at approximately a 16 angle and would comprise a 3 X 2 X Mi inch angle. The support braces would have a cross-section of 4 X 3 X A inch and would be equally spaced about the circumference of the floating roof approximately 5 feet apart. The bolts 34 for bolting the scuff band to the support angle would be disposed approximately 1 foot apart and would be 3 inches off center relative to the support arm. The length of scuff band 42 between the bottom bolting bar or ring 20 and the bolts 34 securing the scuff band to the support angle would be approximately 10% inches. The outside bumper bar 36 would be located approximately 5 inches down from the end of the support arm to insure proper movement of the support arm without pinching the scuff band, and the adjacent ends of the tube as illustrated in FIGS. 3 and 7 would be overlapped approximately 6 feet. The inner bumper bar 37 preferably comprises a flat, rectangular member having dimensions of 2 X l X 54; inches.

An expanding tube seal constructed accordingly would effectively seal a rim space varying from a minimum of 3 inches to a maximum of 15 inches; and as the rim space increases, the support arms 24 pivot outwardly to stay in supporting engagement with the tube; and as the rim space decreases, the support arms 24 pivot inwardly to provide continuous support for the tube 17. The laterally extending bumper 36 suitably fixed to each of the support arms 21 adjacent the upper end thereof would engage the side wall 5 of the storage tank 3 as indicated in full lines in FIG. 4 when the rim space is at a minimum of 3 inches, and the inner bumper bar 37 would engage the support arm 24 and limit inward movement thereof to prevent damage to the tube.

Although the expanding tube seal has been described herein as usedwith a pontoonroof, it could equally as well be used with any other floating roof structure, such as, for example, a double deck roof.

As this invention may be embodied in several forms without departing from the spirit or essential charac-' teristics thereof, the present embodiment isv therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that.

fall within the metes and bounds of the claims or that form their functional as well as conjointly cooperative equivalents, are therefore intended to be embraced by those claims.

I claim:

1. An expanding tube seal for sealing the rim space between a floating roof. structure and a sidewall of a storage tank or the like, comprising an annular flexible tubular sealing ring means, a scuff band means connected to said floating roof ,and at least partially encircling said annular sealing ring means to support said sealing ring means from said floating roof structure, said sealing ring means and said scuff band means disposed in the rim space between the floating roof structure and the side wall of the storage tank, and support means carried by said floating roof structure and in supporting engagement with the bottom of said sealing ring means and scuff band, said support means including a plurality of circumferentially spaced, downwardly extending, rigid support braces secured to said floating roof structure adjacent the bottom thereof, and an upwardly inclined pivotal support arm pivotally connected at one end to each said support brace and in supporting relationship at its other end with said scuff band means and sealing ring means to prevent excessive sag or droop of said sealing ring means and to thereby increase the horizontal reach of said expanding tube seal so as to effectively seal greater rim space.

2. An expanding tube seal as in claim 1, wherein said sealing ring means is filled with a fluid material.

3. An expanding tube seal as in claim 2, wherein said fluid comprises kerosene.

4. An expanding tube seal as in claim 1, wherein said sealing ring means comprises an endless annular tube.

5. An expanding tube seal as in claim 1, wherein said sealing ring means comprises a one-piece tubular memberoverlapped and folded at its opposite ends to define an annular flexible tubular ring.

6. An expanding tube seal as in claim 5, wherein the opposite ends of said tubular member define hollow expansionor accumulator volumes for receiving the sealing fluid to relieve pressure in the tubular member when the sealing fluid expands due to an increase in ambient temperature.

7. An expanding tube seal as in claim 1, wherein said scuff band comprises a plurality of rectangular sections with one end thereof connected to said floating roof structure adjacent an upper marginal edge thereof and the other end of said sections extended substantially around said sealing ring means and connected to a bottom marginal edge of said floating roof structure.

8. An expanding tube seal as in claim 7, wherein said scuff band sections are overlapped at their adjacent edges to define a' continuous support for said sealing ring means.

9. An expanding tube seal as in claim 1, wherein a plurality of arcuate, circumferentially extending support angles disposed in-end-to-end relationship are connected to the upper ends of said support arms and are in supporting engagement with the underside of said scuff band for preventing excessivedroop of said sealing ring means.

10. An expanding tube sealas in claim 9, wherein a support arm is connected at each end of said arcuate circumferentially extending angles so that each angle is supported by a pair of support arms.

l 1. An expanding tube seal as in claim 10, wherein relatively short laterally'outwardly extending bumper means is on each of said support arms adjacent the upper end thereof for engagement with the side wall of said storage tank'to prevent damage to said sealing ring means when said'rim space is at a minimum.

12. An expanding tube seal as in claim 11, wherein said floating roof structure includes a cylindrical outer side wall and a radially inwardly offset clearance recess or notch is in the lower marginal edge of said side wall for providing clearance for said tube seal when a minimum rim space is encountered.

. lower ends thereof to the support braces and in sup- 13. An expanding tube seal as in claim 1, wherein said sealing ring means comprises a plurality of individual tubular bags disposed in end-to-end relationship with adjacent ends overlapped and folded upwardly, the ends of each of the bags being bolted to the top marginal edge of the floating roof.

14. An expanding tube seal as in claim 13, wherein means are connected between adjacent tubular bags to establish fluid flow communication therebetween.

15. An expanding tube seal as in claim 14, wherein said means comprises pipe means-connected between adjacent ends of adjacent tubular bags.

'16. An expanding tube seal as in claim 11, wherein a relatively short, radially outwardly extending inner bumper means is secured at the upper end of each of the support braces for engaging and limiting the inward movement of the support arm to prevent damage to the sealing ring means when the rim space is at a minimum.

17. An expanding tube seal as in claim 1, wherein a predetermined length of said scufi band is fixed between the bottom marginal edge of the floating roof and the support means in supporting engagement with the bottom of the sealing ring means to limit the outward movement of the sealing ringmeans relative to the floating roof.

18. An expanding tube seal as in claim 16, wherein said sealing ring means comprises an endless annular tube, and a sealing fluidin said tube.

19. An expanding tube seal as in claim 16, wherein said sealing ring means comprises a plurality of tubular bags arranged end-to-end in an annular ring and overlapped at adjacent ends, and a sealing fluid in each of said bags.

20. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like, comprising an annular flexible tubular sealing ring means, means connected to said floating roof to support said sealing ring means on said floating roof .structure injthe rim space between the floating roof structure and the side wall of the storage tank, a plurality of circumferentially spaced, rigid, downwardly extending support braces secured to said floating roof structure adjacent the bottom thereof, and

upwardly inclined pivoted support arm means havingupper and lower ends and pivotally connected at the porting relationship at their upper ends with said sealing ring means to prevent excessive sag or-droop of said sealing 'ring means and to thereby increase the horizontal reach of said expanding tube seal so as to effectively seal greater rim space. I

21. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like comprising a one-piece annular flexible tubular sealing ring filled with a fluid material and overlapped and folded at its opposite ends, the opposite ends of the sealing ring comprising hollow expansion or accumulator volumes for receiving the sealing fluid to relieve pressure in the tubular member when the sealing fluid expands due to an increase in ambient temperature, scuff band means connected to said floating roof and at least partially encircling said annular sealing ring to support said sealing ring from said floating roof structure, said sealing ring and scuff band disposed in the rim space between the floating roof structure and the side wall of the storage tank, and I support means carried by said floating roof structure and in supporting engagement with the bottom of said sealing ring'and scuff band to prevent excessive droop of said sealing ring and thereby increase the reach of said expanding tube seal so as to effectively seal greater rim space.

22. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like comprising an annular flexible tubular sealing ring means, a scuff band means connected to said floating roof and at least partially encircling said annular sealing ring means to support said sealing ring means from said floating roof structure, said scuff band comprising a plurality of rectangular sections with one end thereof connected to said floating roof structure adjacent anupper marginal edge thereof and the other end of said sections extended substantially around said sealing ring means andcoh nected to a bottom marginal edge of said floating roof structure, said sealing ring means and scuff band being disposed in the rim space between the floating roof structure and the side wall of the storage tank, and support means carried by said floating roof structure and in supporting engagement with the bottom of said sealing ring means and scuff band to prevent excessive droop of said sealing ring means and thereby increase the reach of said expanding tube seal so as to effectively seal greater rim space.

23. An expanding tube sea] as in claim 22, wherein said support means includes a plurality of circumferentially spaced, downwardly extending support braces connected to the bottom marginal edge of said floating roof structure.

24. An expanding tube seal as in claim 23, wherein a support arm is connected to each of said support braces adjacent the lower end thereof and extends upwardly therefrom in supporting relationship at its upper end with said sealing ring means.

25. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like comprising an annular flexible tubular sealing ring means, said sealing ring means comprising a plurality of individual tubular bags disposed in end-to-end relationship with adjacent ends overlapped and folded upwardly, the ends of each of the bags being bolted to the top marginal edge of the floating roof, a scufl" band means connected to said floating roof and at least partially encircling said annular sealing ring means to support said sealing ring means from said floating roof structure, said sealing ring means and scuff band being disposed in the rim space betweenthe floating roof structure and the side wall of the storage tank, and support means carried by said floating roof structure and in supporting engagement with the bottom of said sealing ring means and scuff band to prevent excessive droop of said sealing ring means and thereby increase the reach of said expanding tube seal so as to effectively seal greater rim space. 

1. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like, comprising an annular flexible tubular sealing ring means, a scuff band means connected to said floating roof and at least partially encircling said annular sealing ring means to support said sealing ring means from said floating roof structure, said sealing ring means and said scuff band means disposed in the rim space between the floating roof structure and the side wall of the storage tank, and support means carried by said floating roof structure and in supporting engagement with the bottom of said sealing ring means and scuff band, said support means including a plurality of circumferentially spaced, downwardly extending, rigid support braces secured to said floating roof structure adjacent the bottom thereof, and an upwardly inclined pivotal support arm pivotally connected at one end to each said support brace and in supporting relationship at its other end with said scuff band means and sealing ring means to prevent excessive sag or droop of said sealing ring means and to thereby increase the horizontal reach of said expanding tube seal so as to effectively seal greater rim space.
 2. An expanding tube seal as in claim 1, wherein said sealing ring means is filled with a fluid material.
 3. An expanding tube seal as in claim 2, wherein said fluid comprises kerosene.
 4. An expanding tube seal as in claim 1, wherein said sealing ring means comprises an endless annular tube.
 5. An expanding tube seal as in claim 1, wherein said sealing ring means comprises a one-piece tubular member overlapped and folded at its opposite ends to define an annular flexible tubular ring.
 6. An expanding tube seal as in claim 5, wherein the opposite ends of said tubular member define hollow expansion or accumulator volumes for receiving the sealing fluid to relieve pressure in the tubular member when the sealing fluid expands due to an increase in ambient temperature.
 7. An expanding tube seal as in claim 1, wherein said scuff band comprises a plurality of rectangular sections with one end thereof connected to said floating roof structure adjacent an upper marginal edge thereof and the other end of said sections extended substantially around said sealing ring means and connected to a bottom marginal edge of said floating roof structure.
 8. An expanding tube seal as in claim 7, wherein said scuff band sections are overlapped at their adjacent edges to define a continuous support for said sealing ring means.
 9. An expanding tube seal as in claim 1, wherein a plurality of arcuate, circumferentially extending support angles disposed in end-to-end relationship are connected to the upper ends of said support arms and are in supporting engagement with the underside of said scuff band for preventing excessive droop of said sealing ring means.
 10. An expanding tube seal as in claim 9, wherein a support arm is connected at each end of said arcuate circumferentially extending angles so that each angle is supported by a pair of support arms.
 11. An expanding tube seal as in claim 10, wherein a relatively short laterally outwardly extending bumper means is on each of said support arms adjacent the upper end thereof for engagement with the side wall of said storage tank to prevent damage to said sealing ring means when said rim space is at a minimum.
 12. An expanding tube seal as in claim 11, wherein said floating roof structure includes a cylindrical outer side wall and a radially inwardly offset clearance recess or notch is in the lower marginal edge of said side wall for providing clearance for said tube seal when a minimum rim space is encountered.
 13. An expanding tube seal as in claim 1, wherein said sealing ring means comprises a plurality of individual tubular bags disposed in end-to-end relationship with adjacent ends overlapped and folded upwardly, the ends of each of the bags being bolted to the top marginal edge of the floating roof.
 14. An expanding tube seal as in claim 13, wherein means are connected between adjacent tubular bags to establish fluid flow communication therebetween.
 15. An expanding tube seal as in claim 14, wherein said means comprises pipe means connected between adjacent ends of adjacent tubular bags.
 16. An expanding tube seal as in claim 11, wherein a relatively short, radially outwardly extending inner bumper means is secured at the upper end of each of the support braces for engaging and limiting the inward movement of the support arm to prevent damage to the sealing ring means when the rim space is at a minimum.
 17. An expanding tube seal as in claim 1, wherein a predetermined length of said scuff band is fixed between the bottom marginal edge of the floating roof and the support means in supporting engagement with the bottom of the sealing ring means to limit the outward movement of the sealing ring means relative to the floating roof.
 18. An expanding tube seal as in claim 16, wherein said sealing ring means comprises an endless annular tube, and a sealing fluid in said tube.
 19. An expanding tube seal as in claim 16, wherein said sealing ring means comprises a plurality of tubular bags arranged end-to-end in an annular ring and overlapped at adjacent ends, and a sealing fluid in each of said bags.
 20. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like, comprising an annular flexible tubular sealing ring means, means connected to said floating roof to support said sealing ring means on said floating roof structure in the rim space between the floating roof structure and the side wall of the storage tank, a plurality of circumferentially spaced, rigid, downwardly extending support braces secured to said floating roof structure adjacent the bottom thereof, and upwardly inclined pivoted support arm means having upper and lower ends and pivotally connected at the lower ends thereof to the support braces and in supporting relationship at their upper ends with said sealing ring means to prevent excessive sag or droop of said sealing ring means and to thereby increase the horizontal reach of said expanding tube seal so as to effectively seal greater rim space.
 21. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like comprising a one-piece annular flexible tubular sealing ring filled with a fluid material and overlapped and folded at its opposite ends, the opposite ends of the sealing ring comprising hollow expansion or accumulator volumes for receiving the sealing fluid to relieve pressure in the tubular member when the sealing fluid expands due to an increase in ambient temperature, scuff band means connected to said floating roof and at least partially encircling said annular sealing ring to support said sealing ring from said floating roof structure, said sealing ring and scuff band disposed in the rim space between the floating roof structure and the side wall of the storage tank, and support means carried by said floating roof structure and in supporting engagement wIth the bottom of said sealing ring and scuff band to prevent excessive droop of said sealing ring and thereby increase the reach of said expanding tube seal so as to effectively seal greater rim space.
 22. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like comprising an annular flexible tubular sealing ring means, a scuff band means connected to said floating roof and at least partially encircling said annular sealing ring means to support said sealing ring means from said floating roof structure, said scuff band comprising a plurality of rectangular sections with one end thereof connected to said floating roof structure adjacent an upper marginal edge thereof and the other end of said sections extended substantially around said sealing ring means and connected to a bottom marginal edge of said floating roof structure, said sealing ring means and scuff band being disposed in the rim space between the floating roof structure and the side wall of the storage tank, and support means carried by said floating roof structure and in supporting engagement with the bottom of said sealing ring means and scuff band to prevent excessive droop of said sealing ring means and thereby increase the reach of said expanding tube seal so as to effectively seal greater rim space.
 23. An expanding tube seal as in claim 22, wherein said support means includes a plurality of circumferentially spaced, downwardly extending support braces connected to the bottom marginal edge of said floating roof structure.
 24. An expanding tube seal as in claim 23, wherein a support arm is connected to each of said support braces adjacent the lower end thereof and extends upwardly therefrom in supporting relationship at its upper end with said sealing ring means.
 25. An expanding tube seal for sealing the rim space between a floating roof structure and a side wall of a storage tank or the like comprising an annular flexible tubular sealing ring means, said sealing ring means comprising a plurality of individual tubular bags disposed in end-to-end relationship with adjacent ends overlapped and folded upwardly, the ends of each of the bags being bolted to the top marginal edge of the floating roof, a scuff band means connected to said floating roof and at least partially encircling said annular sealing ring means to support said sealing ring means from said floating roof structure, said sealing ring means and scuff band being disposed in the rim space between the floating roof structure and the side wall of the storage tank, and support means carried by said floating roof structure and in supporting engagement with the bottom of said sealing ring means and scuff band to prevent excessive droop of said sealing ring means and thereby increase the reach of said expanding tube seal so as to effectively seal greater rim space. 